Step 1: Take the first pictures

get in front of your wall, as this will act as your green screen. Kind of like a chroma key, it will not show up in the final picture. Take a pose, and have somebody snap a picture. My pose wasn't so great becuase i had to take the picture myself, pressing the shutter with my foot. It isn't advised.

Step 2: Get the images\ Fix them up

Look for images on the internet or ones that are already on your computer and open them in Paint.Net. Open one picture and use the magic wand tool to select the wall. Mess around with the tolerance level. Then, delete the wall. After you have just your image, or have deleted most of the wall, wand your main image. You may have to press ctrl and click several differently colored spots of the image, but it's usually pretty quick and easy. Then copy the selected image and make a new page. Past the image on the page. From there make sure the image is still selected and use the erase tool while zoomed in to take out any rough edges if there are some.

Step 3: Invert images

Make a new page and past your background into it. Then resize the images you're going to put in to a size smaller than the image before you copy them and paste them in. You can, however, still copy and paste them into the image and use the arrow tool to alter its size, but if you press off of the image, it flattens and any changes will leave checkered delete marks. These can be solved with ctrl z.

Step 4: Extras

Now to add more than just the characters. Using the same steps, make explosions or whatever. Add superpowers, change peoples' faces to horses, and so on.

you can try to change the tolerance on the wand tool, but if that still doesn't work, you can always use the lasso tool. It will be on the tool selection box along with the wand, and to use it all you have to do is click at some point along the border of the part you want to crop and drag the tool around the border of the part you want cropped. You will see as you get to the other side of you that your picture will start filling in with grey. Just continue draging until you are selected, press ctrl c and make a new page. you can then paste your image. if there is anything else in the part you cropped out that you don't want, you can lasso that too. did this help?

IF you go to Adjustments -> Curves in Paint.NET, you should see a peak near the right hand side of the graph that represents the wall colour. If you raise the curve so that it hits 100% just before this curve then the wall will become pure white. See this page for a great tutorial on how curves work.

That shoulda) make selecting the wall easierb) lighten the images you want to cut out